In this paper we define a simple experimental setup to analyze the behavior of commercial P2P-TV applications under adverse network conditions. Our goal is to reveal the ability of different P2P-TV applications to adapt to dynamically changing conditions, such as delay, loss and available capacity, e.g., checking whether such systems implement some form of congestion control. We apply our methodology to four popular commercial P2P-TV applications: PPLive, SOPCast, TVants and TVUPlayer. Our results show that all the considered applications are in general capable to cope with packet losses and to react to congestion arising in the network core. Indeed, all applications keep trying to download data by avoiding bad paths and carefully selecting good peers. However, when the bottleneck affects all peers, e.g., it is at the access link, their behavior results rather aggressive, and potentially harmful for both other applications and the network.